Combination tool



SepLlS, 1936. J. w. JAMBURA COMBINATION TOOL Original Filed Aug. 21,1934 I BY ATTORNEY Patented Sept. 15, 1936 PATENT OFFICE COMBINATION'rooL John William Jambura, Prairie du Chien, Wis.

Application August 21, 1934, Serial No. 740,820

Renewed July 6, 1936 n 3 Claims. (01. 33-75) The object of thisinvention is to provide a simple, inexpensive and accurate tool whichmay be used for various purposes and which will be of service to'draftsmen, students, architects, mechanics and others. A tool embodyingthe invention is illustrated in the accompanying drawing and will .behereinafter fully described, the novel features being particularlydefined in the appended claims. 5 I

In the drawing:

Figure l is a plan view of the tooltin open position.

Figure 2 is a section on the line 22 of Figure 1.

Figure 3 is a section on the line 33, of Figure 1.

Figure 4 is a section on the line 4-4 of Figure 1.

Figure 5 is a detail plan view of a clamp screw.

The main portion or frame of'the instrument comprises four bars or armsI, 2,3 and 4 which are calibrated in inches as shown. The arms I and 2are each tapered or beveled at one end, 5, and at the opposite ends areprovided with circular extensions 6 which overlap or underlap similarextensions 1 on the arms or bars 3 and 4, re-

spectively. Pivot rivets 8 are fitted centrally through the overlappedextensions so that the arm I will be pivoted to the arm 3 and the arm 2a will be pivoted to the arm 4. The inner end of the arm 3 overlaps theinner endof the arm 4 and is pivoted thereto by a rivet 9, the arm 4having a circular recess in its under side to accommodate the head ofthe rivet, as shown in Figure 3. The arm I is disposed on and crossesthe arm '2 and a studor pin I0 is fitted through said arms at theircenters, the circular head II ofthe stud fitting in a recess therefor inthe under side of the arm 2, as shown in Figure 2. The upper end of thestud projects above the arm I and is threaded to receive a. nut I 2which may be turned home against the arm to hold the several arms in aset position, it being noted that the nut is hollow to house a spring I3which resists loosening movement of the nut but yields readily to apositive force to permit shifting or readjustment of the implement. Theheads of the stud I0 and the rivet 9 are provided with parallel flangesI4 which are undercut, as clearly shown in Figures 2 and 3, to receive agage bar or rule I5 callbrated in inches and having one end, ,IG,pointed and the opposite end, II, square, the pointed end being betweenthe pointed ends 5 of the. arms I and '2. The rule I5 is constructedwith central longitudinal slots I8 and has a central longitudinal lineI9 marked thereon between the slots. The slots and lines cooperate withthe gradua tions of a protractor 20 in a manner which will be laterdescribed.

The protractor 20 is formed on the inner edge of the arm I and isgraduated in degrees along its arcuate edge which is concentric with thestud I ll. semicircles 2I and 22 are marked on the surface of theprotractor and radiallines 23 are drawn at intervals from the edge ofthe protractor to these semicircles and proper numerals are inscribed atthe ends of the lines, the numerals along the inner semicircle beingindicative of the pitch of roof timbers and the numerals along the outersemicircle denoting the number of sides a figure will have when itssides are drawn at the angle indicated by the respectively associatedradii. An indicator or index finger 24 is provided on the arm 2 andprojects over the edge of the protractor to facilitate the reading-of ameasured angle and a line I9 or a slot I8 will bisect the angle andtherefore act as indicators to ascertain half of the angle. 'Notches 25are formed in the edge of the protractor arm I immediately adjacent theouter ends of the protractor to accommodate the indicator when thedevice is fully closed and in other positions of the parts. v

When the tool is collapsed, the protractor arm I will lie over the arm2-and the arms 3 and 4 will be alined and abut the arms I and 2, theprotractorprojecting over and across the arms 3 and 4. The rule I5 willthen project from the armsl and 2 at a right angle thereto and the toolmay then be employed as a T-square. If the rule l5 be withdrawn, thetool may be stored in a small space. The arms 2 and 3 are alwaysparallel and the arms I-and 4 are always parallel, -35 so that the angledefined by the arms I and 2 will always be equal to the angle defined bythe arms 3 and 4 and the rule I5 will always bisect those angles. Whenthe tool is closed, the rule I5 constitutes a convenient marking ordepth gage and it may be slid from the flanges entirelyor partly toavoid interference from the folded arms. The pointed ends of thearms Iand 2 permit the arms to be conveniently used as dividers and compounddividers will be provided by extending the rule I5 until its pointed endalines with the pointed endsoi the" arms. I The accuracy of the pitch ofroof rafters may. be readily determined by resting the extended arms I,2 upon the upper meeting ends of the rafters. The tool may be used in avariety of other ways which will readily suggest themselves as theoccasion arises.

Having described my invention, what I claim 1. A tool comprising aplurality of pivotally connected arms, a semi-circular protractor havinggraduations thereon and carried by one of the arms concentric with thepivotal connection between said arm and the adjacent arm, and a gage barpassing under the protractor and supported by alined pivots of the arms,the gage bar having medial longitudinally disposed means thereon tocooperate with the graduations of the protractor. H

2. A tool comprising a plurality of pivotally connected arms, oppositearms being always parallel, alined pivots connecting the non-parallelarms having overhanging parallel flanges on their

